US 11,786,975 B2
Cutting tool and method for manufacturing the same
Haruko Harada, Osaka (JP); Satoshi Ono, Osaka (JP); Anongsack Paseuth, Osaka (JP); and Katsumi Okamura, Osaka (JP)
Assigned to SUMITOMO ELECTRIC INDUSTRIES, LTD., Osaka (JP)
Appl. No. 17/794,989
Filed by Sumitomo Electric Industries, Ltd., Osaka (JP)
PCT Filed Jan. 25, 2022, PCT No. PCT/JP2022/002579
§ 371(c)(1), (2) Date Jul. 25, 2022,
.
Prior Publication US 2023/0234141 A1, Jul. 27, 2023
Int. Cl. B23B 27/14 (2006.01); C23C 16/36 (2006.01); C23C 16/56 (2006.01); C23C 16/455 (2006.01)
CPC B23B 27/148 (2013.01) [C23C 16/36 (2013.01); C23C 16/45576 (2013.01); C23C 16/56 (2013.01); B23B 2228/105 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A cutting tool comprising a substrate and a coating film disposed on the substrate, wherein
the coating film comprises a first layer formed from a plurality of hard grains,
the hard grains are made of TiSiCN having a cubic crystal structure,
the hard grains have a lamellar structure in which a layer having a first silicon concentration and a layer having a second silicon concentration, lower than the first silicon concentration, are alternately stacked,
the first silicon concentration corresponds to a number ASi of silicon atoms divided by a sum of a) a number ASi of silicon atoms and b) a number ATi of titanium atoms in a grain boundary region between the hard grains, {ASi/(ASi+ATi)},
the second silicon concentration corresponds to a number BSi of silicon atoms divided by a sum of c) a number BSi of silicon atoms and d) a number BTi of titanium atoms in the first layer, {BSi/(BSi+BTi)}, and
a maximum value of ASi/(ASi+ATi) is greater than an average value of BSi/(BSi+BTi).